*{
	margin: 0;
	padding: 0;
	box-sizing: border-box;
}

.box{
	width: 602px;
	height: 602px;
	margin: auto;
/*	border:1px solid black ;*/
}

.row{
	overflow: hidden;
}

.col{
	float: left;
	width: 30px;
	height: 30px;
	border: 1px solid #ccc; 
}
.cf{
	width: 100px;
	height: 28px;
	text-align: center;
	background: white;
	position: absolute;
	top: 50px;
	left: 50px;
}
#dff{
	width: 20px;
	height: 20px;
	background: white;
}
